Android A to Z: What is a QR code?

What is a QR code? These things are everywhere nowadays. Little square barcode-looking things. They're on website, they're on pictures, they're on advertisements -- they're everywhere. So what's a QR code and what do you do with it?

In a nutshell, a Quick Response Code is used to tell your phone to do something. Invented by Toyota in the mid-1990s, they "store" more information than traditional UPC barcodes and work better with languages more complicated than English. (Which is to say, most of them, especially in Asia.)

The way it works is this: Using a scanning app (there's Google's own Goggles app, or plenty of others in the Android Market), your phone's camera scans the code and then interprets it. There are different versions of QR codes, which can contain different amounts of information.

Most often, QR codes are used to link to a website or video or some other online content. Your scanning app should preview the link for you as a safety feature so that you can't be automatically redirected to a malicious (or otherwise untoward) website or video.

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Most of the Android Scanning apps (and Apple too) are also share targets, which means you can share a web address or Contact or Calendar event to your phone's screen as a QR code for your friend to scan.

Fast instant sharing without having to send an email or SMS or give away your email/phone number.

One caveat: Sharing a Calendar event works between Android devices, but share one to an iPhone and the iPhone app drops the timezone conversion and your appointments show in the wee hours for those of us in North America.

This page lets you generate and print QR codes from your computer for a lot of different things: http://www.qrstuff.com/

The WIFI log in is especially useful, because you can share a login but the user never actually gets to see the password. Great for seminars and stuff, but iPhone does not support it, and there is always one of those guys in the crowd.

QR codes are immensely useful. Think about putting one on your business card with your contact info. Great and easy way to add someone's contact info to your phone. http://www.QRCNow.com let's you create a QR code and then print it on business cards, t-shirts, etc.

My favorite is a t-shirt I have with the "Hello my name is" sticker on it and a QR code as the name :-)

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